Transmission



April 5, 1949. E. P. BULLARD m, ET AL TRANSMISSION Filed Apfil 10, 1941 9 Sheets-Sheet l INVENTQRS Edward PHIL llardlfl' B Edward NCuwell ATT April 5, 1949. I E. P. BULLARD m, ETAL 2,466,574

TRANSMIS S ION Filed April 10, 1941 9 Sheets-Sheet 4 lNVEzN l O ATT a Y April 5, 1949. E. P. BULLARD m, ETAL 2,466,574

TRANSMISSION Filed April 10, l94l 9 Sheets-Sheet 5 INVENTO S' Edward PBufimm BY Edward N Con/ell ATTO EY %X .l? 9/ 2 In.

April 5, 1949. E. P. BULLARD Ill, ETAL 2,466,574

. TRANSMISSION Filed April 10, 1941' 7 9 Sheets-Sheet e April 5, 1949.

Filed April 10, 1941 E. P. BULLARD m, ETAL TRANSMISSION 9 Sheets-Sheet 7 |NVENTOR5 EJwani NCou/elZ ATTO Y April 5, 1949. E. P. BULLARD ETAL 2,466,574

TRANSMISSION Filed April 10, 1941 9 Sheets-Sheet a 1 3w EM KNN April 5, 1949. E. P. BULLARD ll], ET AL 2;466,574

TRANSMISSION 9 Sheets-Sheet 9 Filed April 10, 1941 INVENTORS Edwazd .PBulZarzZ. 2F

wycowezz ATTOR- Y Patented Apr. 5, 1949 v TRANSMISSION Edward P. Bullard, III, Fairfield, and Edward N.

Cowcll, Stratford, Conn., assignors to The Bullard Company, a corporation of Connecticut Application April 10, 1941, Serial No. 387,888

24 Claims. 1

This invention relates to transmissions, and particularly to a combined power, and manuallyoperable control for a transmission.

Among the objects of this invention include the provision of a transmission having means adapted to be operated for establishing various gear combinations, and a power-operated control adapted to perform successive cycles of operation, in each cycle of which any of the means for establishing the various gear combinations may be operated; the provision of such a transmission and control, the cycle of operation of the latter of which includes successively performing certain steps in a definitely timed relation; the provision of such a transmission and control in which the latter, during etch cycle of operation, successively neutralizes a main clutch and applies a brake, operates any of the gear-combination establishing means at a time substantially after the engagement of the brake, and disengages the brake and applies the clutch; the provision of such a transmission and control in which any of the means for establishing the various gear combinations may be operated manually without disturbing the setting of the control; and the provision of a transmission including a manually-operable fluid-actuated clutch, the movement of which is definitely proportional to that of the manuallyoperable means therefor.

The above, other objects and novel features of the invention will become apparent upon considering the following specification and accompanying drawings, in which:

Figure 1 is a plan view of the transmission and a control therefor embodyin the principles of this invention;

Fig. 2 is a sectional elevational view taken substantially along the line 2-2 of Fig. 1;

Fig. 3 is a sectional view taken substantially along line 3-3 of Fig. 23 showing a portion of the control mechanism of Fig. 1;

Fig. 4 is an elevational view, partly in section, taken substantially along line 4-4 of Fig. 1;

Fig. 5 is a sectional elevational view taken substantially along line 5-5 of Fig. 4;

Fig. 6 is a sectional elevational view taken sub.-

.stantially along line 6-6 of Fig. 4;

Fig. 7 is a sectional elevational view taken substantially alon line 1-1 of Fig. 4,;

Fig. 8 is a'sectional elevational view taken substantially along line 8-8 of Fig; 4;

Fig. 9 is an end elevational view of the control mechanism as viewed along line 99 of Fig. 1;

Fig. 10 is a sectional elevational view taken substantially along line Ill-l0 of Fig. 9, and showing the apparatus in position for manual manipulation;

Figs. 11 to 22 inclusive are partial sectional views showing the cooperative relation between certain of the various manually-controlled means as viewed along lines to 22-22, respectively, of Fig. 10; and

Fig. 23 is an end elevational view, partly in section, as viewed along lines 2323 of Figs. 1 and 4.

Referring to the drawings, the principles of the invention are shown as applied to a transmission of the type disclosed in application Serial No. 306,122, filed on November 25, 1939, in the names of E. P. Bullard, III, et al. and which has issued as Patent No'. 2,355,624, dated August 15, 1944.

Referring to Figs. 1 and 2, the transmission comprises a driving shaft 25 that is driven from a prime mover- (not shown) through a multiple V-groove pulley 26. The pulley 26 is keyed to an extended hub portion of a spur gear 21 that is journaled in a support 28. The hub of gear 21 is recessed to provide a bearing for the end of the driving shaft 25. The driving shaft 25 supports a multiple-disc friction clutch 29, the discs of which being provided with peripheral teeth. A clutch-driving element 30, having internal teeth adapted to mesh with the teeth on the periphery of the friction discs of clutch 29, is fixed to the gear 21. A friction brake 3| is likewise supported on the drive shaft 25, and comprises a friction disc 32 having peripheral teeth adapted to mesh with internal teeth disposed about an opening in a. fixed supporting bracket 32. Both the clutch 29 and the brake 3| are provided with metal discs on each side of the friction discs and which are splined to the drive shaft 25. A sleeve 33 surrounds the shaft 25 between the clutch 29 and the brake 3|. It supports a slidable grooved spool 34 to which the one ends of toggle connectors 35, 35 are secured, the opposite ends of the connectors being fixed to certain of the movable metal discs of the clutch 29 and brake 3|. Accordingly, axial movement of spool 34 alternately engages and releases the clutch 29 and brake 3|.

The transmission is adapted to drive a driven member 31 at different predetermined speeds throughout a given range. In the present embodiment of the invention, as few gears as possible have been employed for producing the various speeds of rotation of the member 31.

Referring to Fig. 2, the transmission includes a primary unit Pu, a secondary unit .Su and a. tertiary unit Tu. These units are designed and constructed so that only parallel shafts are em- 3 ploycd throughout the transmission, and certain gears are common to various units.

Four spur gears 38, 38, 48 and 4| are freely journaled on the drive shaft and each gear is provided with positive-action clutch-engaging teeth arranged between gears 38, 39 and 48, 4|. Slidable gear-engaging means 42, 43 are keyed to the driving shaft 25 and are located between respective gear sets 38,38 and 48, 4|. Thus, movement of the engaging means 42, 43 to the left or to the right will connect to shaft 25 either gears 39, 4| or gears 3a, 40 respectiveLv. A shaft 44 parallel with shaft 25 is provided in the transmission and is adapted to support four gears 45, 45, 41 and 48 arranged in units of two. These last-mentioned gears are keyed to the shaft 44 and each is retained in constant mesh with gears 38, 38, 48 and 4|, respectively. The gears 38 to 4| and 45 to 48, both inclusive, comprise the primary unit Pu of the transmission.

An additional parallel shaft 48 is provided in the transmission on which gears 58 and 5| are freely -journaled. The gears 58 and 5| are likewise provided with positive-action clutch-engaging .teeth on adjacent sides. A positive-action gear-engaging means 52 is keyed to the shaft 49 and is adapted selectively to engage the gears 58 and 5|. The gear 58 on shaft 49 is adapted to be maintained inconstant mesh with the gear 45 on shaft 44, while the gear 5| on shaft 49 is adapted to be maintained in constant mesh with an additional gear 53 integral with the shaft 44. Gears 45, 58, 5| and 53 comprise the secondary unit Sn. The shaft 44 acts as a common shaft between the primary and secondary units, and gear 45' serves a dual function in meshing with gear 39 of the primary unit and gear 58 of the secondary unit. By selectively shifting the means 42 and 43, shaft 44 can be driven at four separate and distinct speeds from the drive shaft 25. Furthermore, the shaft 48 may be driven at eight separate and distinct speeds from the drive shaft 25 by selectively shifting the means 42, 43 and 52.

The shaft 49 of the secondary'unit is extended and forms one shaft of the tertiary unit Tu. The extended portion of shaft 48 is provided with gear teeth 54 adapted to be maintained in constant mesh with a gear 55 freely journaled on a driven shaft 55 forming the other shaft of the tertiary unit Tu. Likewise, the extended portion of shaft 49 fixedly supports a gear 51 adapted to be maintained in constant mesh with a gear 58 freely journaled on a sleeve 59, which latter is keyed to the driven shaft 55. Each of the gears 55 and 58 is provided with positive-action engaging means facing each other and disposed between the two gears. A shiftable engaging means 58, splined to sleeve 59, is provided between the last two gears for selectively engaging either. In as much as the shaft 49 may be driven at eight different speeds from the driving shaft 25 by shifting means42, 43 and 52, it follows that selectively shifting said means and the means 58 of the tertiary unit Tu will impart sixteen separate and distinct speeds of rotation to the driven shaft 55.

The driven shaft 55 is arranged coaxially with the shaft 44. This arrangement makes it possible to produce an additional four speeds of rotation of the driven shaft 55 from the driving shaft 25 by employing a single additional gear. Accordingly, the gear 53, fixed to shaft 44, is made longer than would be necessary for its proper meshing with gear 5|. The end of driven shaft 55 adjacent the gear 53 is provided with a spline 5|. An internal ring gear 52 is splined on the end of driven shaft 55 and is adapted selec- 4 tlvely to be moved axially by shiftable element 53 to directly connect driven shaft 55 with shaft 44.

From an inspection of Fig. 2,.it is evident that the driven shaft 55 may be driven at 20 different speeds while employing gears that remain constantly in mesh with their-mating gears, thereby avoiding the dilllculties common with constructions employing diving keys. Furthermore, the use of a common shal' t between the secondary and primary units as well as common gears between units, together with the arrangement of the driven shaft 55 coaxial with shaft 44 of the primary and secondary units, tends to reduce to a minimum the number of gears in the transmission for a given number of different speeds of the driven member. Additionally, each gear combination in the primary, secondary and tertiary units is so designed that it may be used with any other gear combination in any other unit and the ability to employ the various gear combinations of each unit over and over, further minimizes the number of gear combinations required for a given number of specific speeds of the driven shaft 55.

The driven shaft 55 is provided with a bevel gear 54 at itsend opposite that which contains spline 5|. This bevel gear 54 meshes with a bevel ring-gear 55 fixed to the under surface of the member 31 to be driven.

The various gear combinations of the transmission are therefore adapted to be established by the operation of the shiftable means 42, 43, 52, 58 and 53. The clutch 28 and the brake 3| are alternately engaged and disengaged by the action of the slidable spool 34. Referring to Fig. 1, a bracket 55 is provided, within which a plurality of rods 51, 58, 59, 18, 1| and 12 are located. These rods are connected to the shiftable means 42, 43, 52, 58, 58 and spool 34 within the transmission through linkages to be described. Accordingly, selective axial shifting of the rods effects shifting of the shiftable means and spool 34 within the transmission.

Referring to Fig. l, the bracket 55 is bolted to the housing containing the transmission. The series of six parallel rods 51, 58, 58, 18, 1| and 12 extend from within the bracket 55 through the transmission housing and are connected to the various shiftable elements of the transmission as follows.

The rod 51 extends to a point on the far side of the transmission and is connected to a lever 13 that is fixed to a vertically-disposed shaft 14. The upper end of the shaft 14 has a lever 15 fixed to it which forms a bell-crank with the lever 13. Lever 15 is connected to a link 15 which in turn is connected to a lever 11 fixed to the lower end of a shaft 18. The upper end of shaft 18 fixedly supports a yoke 18 that engages the shiftable element 42 so that reciprocable movement of the rod 51 moves the element 42 to the right and left thereby selectively connecting gears 38 and 38 to the driving shaft 25.

Rod 58 extends into the transmission housing and is connected to a lever 88 which latter is fixed to a vertically-disposed shaft 8| extending upwardly to a point adjacent the primary unit Pu. Theupper end of the rod 8| rigidly supports a yoke 82, that engages the shiftable element 43.

The rod.58 is pivoted to a lever 53 that is rigidly connected to a vertically-disposed shaft 84. The shaft 84 extends vertically to a point near the top of the transmission. The upper end of shaft 84 fixedly supports'a lever 85 that is pivoted to'a pull-rod 85 connected to an arm of an oscillatable yoke 81. The yoke 81 engages the spool 34 on me driving shaft 25 between the clutch 29 and brake 3 I Rod 10 extends into the transmission housing where it is connected to a lever 88 fixed to a pivot shaft 89. The pivot shaft 69 has rigidly fixed thereto a yoke 90 which is adapted to engage the shiftable element 52 of the secondary unit.

Rod II extends to the far side of the transmission where it is connected to a lever 9I rigidly fixed to a pivot shaft 92. The shaft 92 fixedly supports a yoke 93 that engages the shiftable element 63 for directly connecting the driven shaft 56 to the shaft 44.

The rod 12 is connected to a lever 94 fixed on a pivot shaft 95. The shaft 95 rigidly supports a yoke 96 that engages the shiftable element 60 of the tertiary unit Tu.

From the foregoing it is evident that selective reciprocation of the rods 61, 68, 69, 10, H and 12 will set up various gear combinations and effect shifting of clutch 29 and brake 3| within the transmission to provide twenty difierent rates at which the driven shaft 56 may be rotated.

Referring to Fig. 3, the rods 61, 68, 69, 10, II and I2 are connected to pistons adapted to be reciprocated within cylinders formed in the bracket 66. Inasmuch as each piston and its associated structure for each of the rods is identical with the exception of that for rod 69, only the piston andassociated structure for rods I2 and 69 will be specifically described. The bracket 66 is provided with a cylindrical bore 91 that extends entirely therethrough. The outer end of bore 91 is closed by a plug 98 that is sealed against the leakage of fluid by a nut 99 and packing I00. A piston IOI provided with an integral connecting rod I02 and an integral tail-rod I03 is adapted to be reciprocated within a portion of the bore 91. A closure member I04 is fixedly secured in the inner end'of bore 91 and a member I05 is fixed substantially centrally within said bore. Each of the members I04 and I05 is bored to receive the rods I02 and I03, respectively. The rod 12 is pivotally pinned to the connecting rod I02. The tail-rod I03 is reduced in diameter forming a shoulder I06, and the reduced portion extends into a recess I'l within the plug 98. The end of tail-rod I03 is provided with a collar I08 which forms a shoulder I09 with the portion of tail-rod I03 that is of reduced diameter. The closure members I04 and I define a chamber within which the piston IOI is adapted to be reciprocated. A spacing sleeve H0 is provided between the plug 98 and the closure member I05, defining a chamber within which split piston members III and H2 are adapted to reciprocate. Fluid pressure means, to be described later, is provided for moving piston IOI in either direction, and for constantly supplying fluid under pressure to the chamber in which split piston members III and H2 reciprocate. As shown in Fig. 3, piston IOI is in a position to the right of its central or neutral position. The shoulder I06 has forced the split piston member III to the right while the plug 98 engages and fixes the piston member II2. Upon release of the fluid pressure that has moved piston IOI to the right, split piston members III and H2 will instantly separate and move piston IOI to its neutral position. Upon movement of piston IM to the left as .viewed in Fig. 3, shoulder I09moves member II2 to the left, while the closure member I05 pre vents leftward movement of the member III. Upon release of the pressure that moves piston IN to the left, the portions III and H2 separate thereby neutralizing piston IOI. drilled through the connecting rodl02, piston IM and tail-rod I03 which opens at its one end into the recess I01 and at its other end into the housing of the transmission. The function of hole H4 is to exhaust into the housing of the transmission any fluid that might leak past the several pistons. The piston IOI for rod I2, as well as the corresponding piston for rod 'II is provided with a centrally-disposed annular groove' II5, into which an interference detent H6 is adapted to be forced upon movement of either of the pistons IOI from their central or neutral positions. This interfering device prevents the accidental shifting of either of rods II or l2 when the other is out of its neutral position.

Rod 69 which is adapted to shift the clutch 29 and brake 3|, is pivotally connected to a piston member I I1 adapted to be reciprocated within an elongated cylindrical sleeve II8 fixed within a bore II9 of the bracket 66 by pins I20. The piston member III is provided with a cam surface I2I for a purpose to be described later. It also includes plunger portions I22 and I23 rigidly fixed in spaced relation on a connecting rod I24. A separating element I25 is fixed within the bore of sleeve I I8 and is drilled to receive the connecting rod I24. The construction and arrangement is such thatthe plunger portions I22 and I23 are located on opposite sides of the separating member I25, thereby forming in effect a compound piston arrangement. Fluid-pressure is adapted to be admitted into the space between the plunger portions I22 and I23 and opposite sides of the separating member I25 for shifting the piston Ill and the rod 69in opposite directions for effecting alternate engagement and disengagement of the clutch 29 and brake 3|. A drilled passage I26 extends axially through the rod I24 and piston II! for the purpose of exhausting into the transmission housing any'fiuid that may leak past the plunger portions I22 and I23.

Referring to Figs. 4 and 5, a valve body I2! is mounted on bracket 66 and includes a series of bores I28 extending therethrough, arranged in a common plane and in parallel relation. Valve mechanisms I29, I29, I30, I3I, I32, I32, I33, I33, I34 and I34 are adapted to be reciprocated within said passages I28 for controlling the admission of fiuid under pressure to, and the exhaust from the cylinders in which the pistons IOI are adapted to reciprocate. The pistons IOI which are connected to the rods 12, I0, 68, and 61 are adapted to be moved to opposite sides of a neutral position for shifting the shiftable elements 60, 52, 43 and 42, respectively, within the transmission. Accordingly, these pistons are provided with substantially identical valve actuating mechanism I29, I29, I32, I32, I33, I33 and I34, I34. The piston IOI that is connected to the rod II is adapted to be moved to only one side of a neutral position and accordingly, only a single valve actuating mechanism I30 is provided therefor. The valve actuating mechanism I3I is employed for a purpose to be described later.

The valve body I2! is provided with a passage I35 in which a compound valve-'actuatingmechanism I36 is adapted to be reciprocated for controlling the admission of fiuid under pressure to, and the exhaust from the piston II! that is adapted to effect shifting of the clutch 29 and brake 3I. In order to supply all of the valve actuating mechanisms with fluid under pressure,

A hole I is a passage I31 is provided that extends throughout the length of the valve body I21 and which order to by-pass the fluid under pressure around the valve mechanism I36, passage I35 is provided with a counter-sunk portion I38 at its bottom extremity, namely at the dividing line between the valve body I21 and the bracket 66, and a pair of holes I39 are drilled from the counter-sunk portion I38 to the passage I31.

The bracket 66 is additionally provided with a passage I40 that extends throughout its entire length and with which each of the passages I28 communicates. The passage I40 exhausts to the transmission housing through a series of spaced parallel ducts I40. The opposite ends of passage I40 are provided with plugs I, as are all of the openings in the valve body I21 and bracket 56 that are formed by drills and which require a sealing means. From the foregoing, it is apparent that fluid passing through an inlet I42 of the valve body I21 is distributed to all of the valve actuating mechanisms within the valve body.

Inasmuch as the construction and operation of the valve mechanisms I29, I29, I32, I32, I33, I33, and I34, I34 are identical, only the construction and operation of the valve mechanism I29, I29 will be specifically described.

Referring to Fig. 5, the passage I28 is provided at its lower extremity with a tubular insert I43 having a scalloped upper edge I44 in registry with the fluid inlet passage I31. A passage I45 is provided in the block I21 which communicates with a drilled hole in the side of the tubular element I43. Passage I45 communicates with passages I46 and I41 which latter opens into the bore 91 on the left side of the piston IOI as viewed in Fig. 5. Another passage I48 in the valve body I21 is in registry with the inlet I31 between the adjacent bores I28 in which valve mechanisms, I29, I29, reciprocate. Passage I48 communicates with passages I49, I50, II and delivers fluid under pressure to annular space I52 formed between the split piston members III and H2.

The valve-actuating mechanism I29 comprises two parts, a lower part I53 and an upper part I54. The lower part I53 includes a plunger portion I55 that is adapted to be reciprocated within the passage I28 and to seat on top of the scalloped edge I44 of the tubular member I43. Member I53 also includes a downwardlyextending valve stem I56 on the lower end of which is provided a valve member I51. In the position of the lower portion I53 as shown in Fig. 5, wherein it is seated on the top of the scalloped edge I44 of the tubular member I43, it is evident that fluid under pressure enters the center of the tubular member I43 from the passage I31,

passes through the passages I45, I48 and I41.

into the bore 91 on the left hand side of piston IOI thereby forcing said piston to the right. Likewise, fluid pressure is admitted from duct I31 through the passages I48, I49, I50 and I5I to the annular space I52 formed between the split piston members I II and H2. Even though this pressure is the same as that which acts on piston IOI, the differential area between the piston IOI and the piston members III and H2 is such that the latter is overcome by the former and-the piston IOI moves to the right. Upon 8 release of the force which holds the portion I53 in its lower position, the pressure from inlet I31 acts on the area of plunger portion I55 adjacent the scalloped portion I44 of tubular member I43, which area is greater than that of the valve member I51 against which said pressure also acts. Accordingly, the lower portion I53 of the valve mechanism I 29 is raised to an upper position, cutting oi the passage of fluid from inlet I31 to passage I45 and permitting the fluid trapped within the bore 91 on the left side of piston IIlI to by-pass the valve I51 to the exhaust passage I40, thence the exhaust passes through one of the ducts I to the interior of the transmission housing. Immediately upon cutting ofi the inlet pressure from passage I31 to the passage I45, split piston members III and H2 are separated as previously explained thereby moving piston IOI to its neutral position.

Fluid under pressure is admitted in an identical manner to the right side of piston IOI in the space formed between it and the left side of closure member I05 by the valve actuating mechanism I29 (Fig. 4) as follows. A passage I59 (Fig. 5) is provided in the valve body I21 which communicates'with a tubular member within the passage I28 that receives valve-actuating mechanism I29 in the same manner that passage I communicates with the interior of the tubular member I43. Passage I59 communicates with passages I00 and I5I which latter delivers fluid into the space formed between the right and left hand faces of the piston IN and the closure member I 05, respectively. From the foregoing it is evident that movement of the valve actuating mechanism I29 to its lower position permits the fluid under pressure from passage I31 to flow through the ducts I59, I80 and lil into the bore 91 on the right side of piston IIII thereby forcing piston IOI to the left. Upon release of the force holding the actuating mechanism I 29 in its lower position, its lower portion moves upwardly and exhausts the fluid trapped on the right side of piston IM to the passages I40 and I 40'. When this occurs, of course, the pressure acting on the split piston members III and I I2 instantly separates them thereby effecting movement 'of piston IM to its neutral position.

The upper portion I54 of 'the valve-actuating mechanism I29 includes a stem portion I82 and an abutment portion I03 which latter is adapted to be engaged by means to be described later for forcing the portion I54 downwardly. The abutment portion I 63 includes a shoulder I54 that is adapted to engage shoulders formed between a series of narrow removable plates I 63' that form the top of valve body I21. The upper portion of the valve-actuating mechanism I2! is identical with that of mechanism I29. From the foregoing it is apparent that the selective depression of the valve-actuating mechanisms I29 and I29 will cause the piston IOI tobe moved to either side of its neutral position thereby effecting the shifting of shiftable element of the transmission. In an identical manner, the selective depression of the valve-actuating mechanisms I32, I32, I33, I33, and I34, I34 efiects the shifting of rods 10, 68 and 81, respectively, to thereby shift the shiftable elements 52, 43 and 42 of the transmission.

Referring to Fig. 6, the valve mechanism III is identical with the valve mechanism I29 (Fig. 5). Movement of the mechanism I30 to its lower position admits fluid from the inlet I31 to the left side of the piston IOI that is connected to the rod 1I, thereby forcing said piston to the ,right to shift element 63 of the transmission position, pressure from the inlet I31 will eflect/ the upward movement of the valve I30 in the same manner as it moves the valve mechanism I29 to its upper position. In its upper position,

valve I30 exhausts the fluid trapped on the left side of piston IM to the passage I40, while at the same time, pressure from the inlet I31 that is continuously acting upon the split piston members III and H2 of the assembly disclosed in Fig. 6, moves the piston IM to its neutral position. The closure member I05 in this instance is provided with a groove I05 in communication with a radial passage I64 that leads to the exhaust passage II4 extending through the piston I0! and its connecting and tail-rods. This construction permits the exhausting of any fluid that may leak past the piston IOI and become trapped on the right side thereof.

Referring to Fig. 7, the valve mechanism I36 within the bore I35 of the valve body I21 is designed for dual functioning, namely, for manual as well as automatic operation. Although the specific construction of the valve mechanism I36 is essentially for manual manipulation of the apparatus, it also functions automatically. Even though its significance relative to manual manipulation of the apparatus will not appear until later, its specific construction will now be described. Essentially, the valve mechanism I36 comprises a sleeve I64 fixed within the bore I35,

8. vertically-reciprocable sleeve I65 mounted within the sleeve I64, and a vertically-reciprocable'valve stem I66 mounted within sleeve I65.

A cam follower I61, adapted to cooperate with the cam surface I2I of the piston H1, is provided with a plug extending up into the verticallyreciprocable sleeve I65 and which is fixed to said sleeve by a pin I68.

Referring to Fig. 4, the countersunk portion I38 of the bore I35 that communicates with passages I39 and inlet passage I31 is also adapted to communicate with radial passages I69 that extend through the fixed sleeve I64.

Referring again to Fig. 7, radial passages I69 communicate with an annular chamber I formed between the sleeves I64 and I65. Radial passages I1I that extend through the sleeve I65 provide communication between the interior of sleeve I65 and said annular chamber I10. The vertically-reciprocable valve, stem I66 is provided with an axial bore I12 extending partially therethrough, and a radial passage I13 near its upper end, at the dead end of said bore. The radial passage I13 communicates with a chamber I14 formed between the slidable sleeve I65 and the stem I66. The construction and arrangement is such that-slight downward movement of the valve stem I66 will effect separation of a contact point I15 between the valve stem I66 and the sleeve I65. Such separation provides communication between the annular chamber I 14 and another annular chamber I16 formed bet-ween the sleeve I85 and the stem I66. The sleeve I65 is provided with radial bores I11 that communicate with an annular chamber I18 formed between the slidable sleeve I65 and the fixed sleeve I64. A radial bore I19 is provided in the fixed sleeve I64 in alignment with a passage I80 formed in the valve body I21. A verticallydisposed passage I8I, within the valve body I21,

10 is in communication with the passage I80 and also with a passage I82 formed in the bracket 66. The passage I82 in bracket 66 communicates, with a passage I83 that opens into the space between the separating element I within the cylinder H8 and the right hand side of piston II1. Accordingly, the downward movement of the valve stem I66 permits the fluid under pressure from port I69 to pass upwardly through passage I12, through port I13 into chambers I14, I16, through port I11 into chamber I18, thence through port I19 into passages I80, I8I, I82, and I83 into cylinder II8 on the right hand side of piston III causing the same to be moved to the left. Slight leftward movement of piston II1 tends to move the cam surface I2I away from the cam follower I61. However, the fluid under pressure entering the ports I'II of the slidable sleeve I65 acts upon the upper face of the plug connected to cam follower I61 and causes downward movement of the cam follower and sleeve I65. Slight downward movement of the sleeve I65 causes re-engagement of the sleeve I65 and stem I66 at point I15 thereby cutting off the supply of fluid under pressure from chamber I14 to chamber I16, whereupon the' assembly assumes the position shown in Fig. 7. Continued downward movement of the valve stem I66 again effects separation of the contacting point I15 re-establishing communication between the chambers I14 and I16 whereupon continued leftward movement of the piston II1 occurs. However, sleeve I65 is again lowered by virtue of cam surface I2I moving to the left causing re-engagement of the sleeve I65 and stem I86 at point I15 therebystopping the leftward movement of piston I I1. This intermittent supplying of fluid under pressure to chamber I16 efiects an incremental movement of piston II1 until the shiftable rod 69 is moved to its maximum leftward position. However, as will appear later on, such action only occurs during the manual operation of the valve mechanism I36 since during automatic operation, the valve stem I66 is moved instantly to its lowest position causing instant and complete leftward movement of the piston I I1.

Upon release of the force that has moved stem I66 to its lowest position, the fluid pressure entering sleeve I65 through ports I1'I acts upon an annular surface I84 at the bottom of the stem I66 causing the same to move upwardly. Slight upward movement of the valve stem I66 effects the separation of the sleeve I65 and stem I66 at a point I85, whereupon chamber I14 communicates with an annular chamber I86 formed between the sleeve I65 and the stem I 66. Radial ports I81 extend through the walls of sleeve I65, and communicate with an annular chamber I88 formed between the slidable sleeve I65 and fixed sleeve I64. A passage I89 formed in the valve body I21 communicates with the chamber I88 and also with a vertically-disposed passage I90 that extends downwardly in parallel but spaced rela tion with respect to the passage NH. The vertically-disposed passage I90 communicates with a passage I9I in the bracket 66 which latter passage communicates with a groove I92 in the separating member I25 within cylinder II8. Groove I92 in turn communicates with the space formed between the right face of separating member I25 and the left face of plunger portion I23. Accordingly, upon slight upward movement of stem I66, fluid under pressure is adapted to pass from chamber I14 to chamber I86, port I81,

11 chamber I86, passages I89, I98, I9I, I92 and to act upon the left face of plunger 'member 28 causing plunger 1 and rod 69 to move to the right. Slight movement of plunger ill to the right causes cam surface I2I to act against follower I61 forcing vertically-reciprocable sleeve I65 upwardly whereupon the sleeve I65-and stem I86 re-engage at point I85 thereby cutting off the supply of fluid under pressure to chamber I86 and stopping the rightward movement of piston H1. The upward movement of stem I66 is continuous and the sleeve I65 follows it upwardly until both slidable members reach their maximum upward position where they remain until further downward movement of the stem I66. At all times, the slidable members I65 and I66 tend to assume the position shown in Fig. 7. Slight upward movement of valve stem I66 not only separates the sleeve I65 and stem I66 at the contest point I85 to admit fluid under pressure to the left side of piston member I28, but it also separates a contact point I85 between said stem I66 and sleeve I65, whereupon chamber I16 communicates with a chamber I88 formed between the stem I66 and sleeve I65. Radial pasmember is provided with dove-tail grooves for receiving replaceable plates I96 that are adapted to support shoes I91 for engaging the abutment portions I68 at the upper ends of the various valve-actuating mechanisms. The plates I98 are fixed in place on the program drum I98 by screws I98. The shoes I91 on plates I96 on the right side of the groove I95 (Fig. 4) are adapted to control the valve actuating mechanisms I88, I88 and I84, I84, which in turn control the admission of fluid pressure to, and exhaust from the opposite sides of the pistons I8I that are connected to rods 61 and 68, the movement of which controls the shiftable elements 42 and 48 of the primary unit Pu of the transmission. The shoes I91 on plates I96 on the left side of the groove I95 are adapted to control the shifting of shiftable elements for the secondary unit Su, tertiary unit Tu and the direct drive. Various combinations of the .plates I98 may readily be assembled to provide a definite program, and upon the successive indexing of the drum I98, a succession of sages I8I' are provided in the sleeve I65 which communicate with a chamber I82 formed between the sleeves I64 and I65. A radial passage I88 in sleeve I64 opens into the exhaust line leading to the transmission housing. Accordingly, as the piston II1 moves to the right, fluid trapped between it and the left side of partition I25 exhausts through passages I88, I82, I8I, I88, through port I19 into chamber I16, through port I11 into chamber I16, thence into chamber I88, through port I8I', into chamber I82, through port I88 to the transmission housing. Additionally, as the stem I66 moves downwardly,

- it not only causes separation of sleeve I65 and stem I66 at contact point I15, but also causes separation of a contact point I15 between said stem and sleeve. Accordingly, upon downward movement of stem I66, any fluid trapped between the right and left faces of members I25 and I28,.

. causing piston II1 to move to the right which disengages brake 8i and engages clutch 29.

The selective depression of valve mechanisms I28, I28, I88, I82, I82, I88, I88, I84 and I84 is effected by the step by step movement of a progrsmdrum I88 (Fig.4) thatisadaptedtobe indexed about a horizontal axis. The drum I88 is positioned directly above the valve body I21 such that its axial center line is in the same plane as that which contains the valve mechansm for the pistons MI. The program drum I98 comprises a polygonally-faced member in which a groove I95 is formed to provide a space for the means that actuates valve mechanism I86, to be described later. trunnions iournaled in bearings I94 and I94 formed on brackets mounted on the body I21. Each of the faces of the polygonally-shaped different rates of rotation of the driven shaft 56 of the transmission may be effected.

Prior to the changing of any gear combination within the transmission, it is necessary to disengage the clutch 29 and to engage the brake 8| in order to stop the transmission; and upon effecting a new gear combination within the transmission, it is necessary to disengage the brake 8I and tone-engage the clutch 29.

- Referring to Figs. 1, 4 and 9 and particularly Fig. 9, 8. Geneva stop wheel "I is provided with as many radial slots 282 as there are sides to the polygonally-shaped drum I98. This wheel 28I is flxed to the end of one of the trunnions of the program drum I98 by a washer 288 and a lock bolt 284. An indexing disc 285, provided with a I011 286 adapted to cooperate with the radial grooves 282, is mounted on a shaft 281 parallel with but spaced from the trunnions of the program drum I98. The disc 285 is adapted to be rotated in a clockwise direction. and is provided with means forming a time-delay actuating mechanism for controlling the admission of fluid under pressure to the piston I I1 for shifting the clutch 29 and brake 8I. A shaft 288 mounted The drum is provided with in brackets at the back of the valve body I21 is adapted to extend throughout substantially the entire length thereof (Fig. 1). The shaft 288 fixedly supports a rocker arm 289 within the groove I (Fig. 4) and in alignment with the valve-actuating mechanism I86. Referring to Fig.9, the end of the shaft 288 rigidly supports an arm 2I8 having a follower 2 in the plane containing the disc 285. The follower 2 is adapted to ride'on the periphery of disc 285. The fluid pressure continuously urging the valve stem I88 of the valve mechanism I88 upwardly, forces therocker arm 288 upwardly and consequently the arm 2" towards the disc 285 such that the roller 2 is maintained in constant engagement with the periphery of said disc 285.

A recessed portion 2I2 is formed in the periphery of the disc 285 within which follower 2 II normally rests. The construction and arrangement is such that as the disc 285 initially moves in a clockwise direction from the position shown in Fig. 9, the shaft 288 is turned in a counterclockwise direction thereby depressing the valve stem I66 of the valve mechanism I86. The roll 286 however does notengage the next succeeding radial slot 282 of the Geneva stop wheel 28I for a substantially long time interval after the depression of valve mechan sm I88. Accordingly,

transmission.

tate, roll 206 engages a slot 202 in the Geneva wheel 20| and indexes the program drum one step. Upon the completion of the indexing movement of the program drum I 93, the recess 2I2 returns to cooperative position with the roll 2| I,

thereby permitting the fluid under pressure to;

raise the valve means I36 effecting disengagement of the brake 3| and re-engagement of the clutch Referring to Figs. 1 and 4, power is supplied to the disc 205 through a motor 2|3 and a gearreduction unit. The circuit of the motor 2|3 in- Upon closing the push button switch, the motor 2 I 3 begins to rotate and to drive the disc 20-5 in a clock- .wiseldirection. A cam disc 2I6 fixed to rotate with disc 205 is provided with a notch 2" into which the one end of a lever 2I8 is resiliently urged. Upon the beginning of rotation of the disc 205, the lever 2I8 is'moved in acounterclockwise direction closing holding switch 2| 5 and maintaining it closed after the release of the push button switch. Upon the completion of a single revolution of the disc 205, when roll 2| I is within the recess 2 I2 again, lever 2 I8 cooperates with groove 2" thereby effecting the opening of holding switch 2I5 and stopping motor 2I3.

In order to prevent vibrations from changing the position of the program drum I 93 between successive indexing movements, a lever 2 I9 (Figs. 4 and 8) is journaled on the shaft 208. A spring pressed member 220 mounted in the valve body I21 is adapted to resiliently force the lever ,2I9 upwardly into engagement with the sides of the polygonally-shaped drum I 93. Referring to Figs. 1 to 5, inclusive, the program drum"-I93 is shown in position such that valve mechanisms I29, I32 and I33 are depressed to their lower positions. With valve mechanism I29 in its lower position, fluid is admitted under pressure to the left side of the piston that is connected to rod 12 thereby shifting element 60 of the transmission to the right (Fig. 1) connecting gear 55 to driven shaft 56. Valve mechanism I32 in its lower position admits fluid under pressure to the left side of the piston |0| that is connected to the rod 10 thereby shifting element 52 of the secondary unit Su to the left (Fig. 2) connecting gear to shaft 49. Valve mechanism I33 in its lower'position admits fluid under pressure to the left side of the piston |0| connected to the rod 68 thereby shifting element 43 of the transmission to the left connecting gear 4| to shaft 25. Referring to Fig. 2, th gear train that is established in the transmission by the control mechanism in the position shown in,

Fig. 4 is such that power is transmitted-from shaft .25 to gear 4|, gear 48, thence through gear 53 to gear 5|, and finally from gear 54 to gear 55. Upon indexing the program drum I93, the shoes I91 are so located that valve mechanism I29 is moved to its lower position while valve I29 is permitted to move to its upper position; valve mechanism I32 is lowered while valve mechanism I32 is permitted to rise; and valve mechanism I33 is lowered while valve mechanism I33 is elevated, Accordingly, upon indexing drum I93 to its next succeeding position, fluid under pressure will be admitted to the right side of the piston |0I connected to the rod 12 whereupon .cludes a push button switch (not shown), in parallel with a holding switch 2 5 (Fig. 9).

shiftable element 60 of the transmission is moved' to the left (Fig. 1) connecting gear 58 to shaft 5B; fluid pressure is admittedto the right side of the-piston |0 I connected to the rod 10 whereuponthe shiftableelement 52 of the secondary unit Su is shifted to the right connecting gear I mission,. and the control (including drum. I93,

Geneva stop-2M, disc 205 and attending apparatus) is adapted to perform successive cycles of operation (neutralizing clutch-29, applying brake 3|, indexing drum I93 at a time substantially after brake 3| has been applied, disengaging brake 3| and engaging clutch 29), in each I cycle of which any-of the means for establishing operative gearv combinations is adapted to be actuated.

The present invention contemplates the provision of mechanism for manually selecting various gear combinations within the transmission without disturbing the setting of the program drum I93. In other words, the invention includes means associated with the program drum I93 for rendering effective, manually-operable means for shifting the shiftable elements within the transmission which means is adapted to become effective at the end of a predetermined program of operation of the transmission.

Referring to Fig. 10 the valv body I21 is provided with bores 22| and'222 arranged in parallel relation, extending throughout the entire length thereof and. adapted to receive valve plugs 223 and 224. The valve plugs 223 and 224 comprise elongated cylindrical members having bosses 225 formed thereon through which ports extend from the exterior thereof to a passage 226 drilled .axially of said plugs. -The outer surfaces of the bosses 225 are machined to accurately fit the bores 2.2I and 222, and said bosses are arranged in such manner that they cooperate with means to be described later for controlling the admission of fluid under pressure to, and for exhausting the fluid under pressure from the operative sides of the pistons |0| for effecting shifting of the shiftable elements within the transmission. Closure members 221 and 228 are fixed to the sides of the valve body I21 and bearings are formed therein for receiving and journaling parts of the plug valves 223 and 224. Each of the plug valves 223 and 224 is providedwith flanged portions 233 that are axially. spaced and of a diameter accurately fitting the bore 22| and 222.

various bosses 225 onthe exterior of the plug 15 valves"223 and 224 form exhaust chambers with the bores 22I, 222. Communication between the bores 22I, 222 for said exhaust chambers on the.

bore 222. A passageg243 (Fig. 13) is provided.

within the valve body I21 that leads to the housing of the transmission, to which the exhaust fluid from the left hand side of flanges 233 in bores 22I, 222 is returned. A passage 233 is provided in the body I21 for exhausting the fluid from the right hand side of flanges 233 in bores 221, 222 into chamber I11 (Figs. 7 and 18) thence to the housing of the transmission.

From an inspection of Fig. 10 it is evident that substantially perfect alignment between the bore 222 and that for bearing 229 must be provided since the bosses 225 and the flanges 233 on the plug valve 224 must accurately flt said bore 222. Perfect alignment of the axes of the bore for bearing 229 and the bore 222, is provided. and the arrangement includes forming the bearing 233 for the rear end of the plug valve 224 without regard to precise alignment between it and the bore 222 and bearing 223. The end of plug valve 224 opposite that journaled in bearing 229 is provided with a pin receiving slot 24 I, and a trunnion within bearing 233 is provided with a similar slot 242. A shaft 243 extends between the trunnion within bearing 233 and the end of plug valve 224 containing pin slot 24I. Shaft 243 is provided with pins adapted to engage the respective slots 2 and 242, thereby producing a construction that will permit slight misalignment of the axis of bearing 233 with those of bearing 229 and bore 222. A similar construction is employed in connection with the plug valve 223 as clearly shown in Fig. 10.

Handwheels 244 and 245 are connected to the extensions of the plug valves 224 and 223 that are journaled in bearings 229, 23I. These handwheels contain numbers 1 to 4 and letters A to E (Fig. 9). The numerals 1 to 4 represent the four rotative positions plug valve 224 is adapted to assume, while the letters A to E represent the flve rotative positions plug valve 223 is adapted to assume. Accordingly, rotation of the hand wheels 244 and 245 will effect rotary movement of the plug valves 223 and 224 for controlling the ad'- mission of fluid under pressure to the various pistons I3I in a manner to be described later.

Referring to Figs. 4 and 8, the valve mechanism I3I is adapted to control the admission of fluid under pressure to the plug valves 223 and 224 (Fig. 10). Referring particularly to Fig. 8, the valve mechanism I3I is identical with the valve mechanism I29 (Fig. 5). Movement of the mechanism I3I to its lower position will permit fluid under pressure from the inlet I31 to flow past the valve head I51 into a passage 245 that communicates with-the vertically-disposed passage 231 that leads to the recesses 234 between the flanges 233 of the plug valves 223 and 224. Upon release of the force which holds the valve'mechanism I3I in itslower position, the same will be caused to move upwardly in the same manner that valve mechanism I29 is caused to move upwardly upon release of the force which holds it in its lower position, and the fluid under pressure within the cylinders of the pistons I3I will be exhausted into the exhaust passage I43 via passages 231 and 246; In order to exhaust any fluid that may leak past the lower portion of 16 f valve mechanism I3I, the valve body' I21 is provided with a passage 241 in communication with a vertically-disposed passage 243 that communicates with the exhaust passage I40.

Referring to Fig. 4. it is evident that the program drum I93 must be indexed four times before the shoe I91 in alignment with valve mechanism I3I cooperates therewith to move it to its lowest position. During the successive four indexes of the program drum I 93, separate and distinct gear combinations will be set up within the transmission. For purposes of clarity, the hand wheels 244 and 245 (Fig. 10) have been set to establish the same gear setting that is efl'ected by the position of the program drum I33 in Fig. 4, and, accordingly, uponthe fourth successive index of the drum I93 from the position in which it is shown in Fig. 4. valve mechanism I3I will be moved to its lower position and a gear combination identical with that effected by virtue of the downward movement of the valve mechanisms I 29, I32, and I33 will be established. Fig. 10 discloses the apparatus in a position where the valve mechanism I3I is in its lower position with the handwheels 244, 245 set as above described.

Referring to Fig. 5, the valve mechanism I23, etc., were previously described as comprising an upper portion I54 and a lower portion I53. These portions are independently movable such that the lower portion I53 can be moved downwardly against the seat on the upper edge of tubular member I independently of the movemen-t of the upper member I54. The upper member I 54 is prevented from moving upwardly beyond a fixed point by virtue of the shoulder I54"formed between the abutment portion I33 and the stem portion I54, which shoulder engages the plates I53'.

Referring to Figs. 5 and 11, the valve body I21 is provided with a passage 253 that is adapted to communicate with the passage I28 within which the valve mechanism I23 is adapted to reciprocate. Passage 253 also communicates with the bore 22I within which plug valve 223 is adapted to be oscillated. The boss 225 (Fig. 11) is provided with two radial ports 25I and252 that are adapted to be moved into alignment with the passage 253. When this occurs, fluid under pressure from the passage 226 is delivered into the bore I23 between the upper and lower portions I54 and I53 of the valve mechanism I23, thereby i'orcing the lower portion I53 downwardly until it seats on the upper edge of the tubular member I43 and permitting the pressure from inlet I31 to be admitted to the left side of the piston I3I connected with the rod 12, thereby effecting the shifting of element 53 to engage gear 55 to the driven shaft 53 of the transmission. Counter-clockwise movement of the plug valve 223 will align radial passage 252 with passage 253 and likewise cause shifting of element 53 to engage gear 55 with the driven shaft 55 of the transmission. An exhaust passage 25I is provided for each of the bores I23 that receive fluid under pressure for manual manipulation. The passage 25I communicates with an annular. chamber 252' formed between the stem I52 and the bore I23 for exhausting any fluid that might lead: past the upper portion I54 of the valve mechanism and thereby preventing such fluid from leaking out on top of the plates I33.

Referring to Fig. 12, the boss 225 shown therein is provided with two radial passages 253 and 254 which upon continued counter-clockwise movement of the plug valve 223 will come into I line with a passage 258' parallel with but spaced fluid under pressure from passage 228 is admittedto the right hand side of the piston I8I connected with the shiftable rod I2 thereby to effect engagement of shiftable element 58 of the transmission with gear 58 thereof. Accordingly, four positions of rotation of the plug valve 223 will provide the selective shifting of the shiftable element 88 to effect its engagement with gears 55 and 58.

Referring to Figs. 6 and 14, the plug valve 223 is provided with a single radial port 255 that is adapted to be turned into alignment with a passage 258 communicating with the bore I28 within which valve mechanism I38 is adapted to be reciprocated. When the radial port 255 is in alignment with the passage 258, fluid und'er pressure is adapted to move the lower portion of valve mechanism I38 downwardly until it seats upon the tubular member I43 thereby admitting fluid under pressure to the left side of the piston I8I connected to the rod II and effecting the movement of element 83 to engage the direct drive between shaft 44 and the driven shaft 58.

Referring to Fig. 16, the plug valve 223 is provided with two additional bosses 225 in which radial ports 251 and 258 are located. The ports 25! and 258 are adapted" to cooperate with passage 258 that communicates with the bore I28 within which the valve mechanism I32 is adapted to be reciprocated. In the position shown in Fig. 16, passageway 25! is in alignment with the passage 258 thereby admitting fluid under pressure from the axial bore 228 to the valve mechanism I32 and forcing the lower part of the valve mechanism I32 downwardly to admit fluid underpressure to the left side of the piston I8I that is connected to the rod I8, thereby shifting the element 52 of the transmission into engagement with the gear 5 I. Similarly, when the radial passage 258 is in alignment with the passage 258, the same condition prevails, namely, shiftable element 52 of the secondary unit Sn is shifted into engagement with gear 5|.

Referring to Fig. 1'7, theplug valve 223 is provided with three bosses 225 in which radial passages 288, 26I and 282 are located. These passages are adapted to cooperate with a passage 253 that is formed in the valve body I21 and which communicates with the bore I28 within which the valve mechanism I32 is adapted to reciprocate. When the radial passages 288 and 28I are in alignment with the passage 283, fluid under pressure forces the lower part of valve mechanism I32 downwardly, whereupon fluid under pressure from inlet I3! is admitted to the right side of the piston I8I that is connected to the rod [8 thereby effecting engagement between the shiftable element 52 and the gear 58 within the transmission.

Referring toFigs. 11, 12, 14, 16 and 17, attention is directed to the fact that the radial ports 25I and 251 are aligned with their respective passages 258 and 258 at the same time. Thus, gear 55 is connected to the driven shaft 58 and gear 5I is connected to shaft 48 whereupon the drive from the primary unit Pu passes through the gears 53, 5|, 54 and 55 to the driven shaft 58. Furthermore, radial ports 253 and 258 will become aligned with their respective passages 258 and 258 at the same time, in which case gear 58 will be connected to the driven shaft 58 and gear 5| will be connected to shaft 48. In this case the drive from the primary P will include gears 53, 5|, 5! and 58. Furthermore, radial ports 252 and 288 wfll become aligned with their respective passages 258 and 283 at the same time. When this occurs, gear 55 will be connected to the driven shaft 58 and gear 58 will be connected to shaft 48. The drive then will be from the primary unit through the gears 48, 58, 54', 55. Additionally, the radial ports 254 and 28I will become aligned with their pasages 258' and 283 at the same time. ,When this occurs, gear 58 is flxed' to the driven shaft 58 and gear 58 is connected to shaft 48. Accordingly, under these circumstances the drive from the primary unit will include gears 48, 58, 51, and 58. From'the foregoing it is evident that four positions of the plug valve 223 will provide four separate and distinct gear combinations within the transmission and a fifth combination, 1

namely, the direct drive will be established when the passage 255 (Fig. 14) is aligned with the passage 258 in which case, element 82 is shifted into engagement with the gear 53 thereby directly connecting the driven shaft 58 with the shaft 44. Should the direct drive be established for a great length of time, the driven shaft and the bushing for gear 58 will be subjected to'excessive unequal wear tending to make them eccentric. This has been overcome by providing the additional radial port 252 (Fig. 1'1) which will automatically become aligned with passage '283 at the same time that the radial port 255 (Fig. 14) becomes aligned with its passage 258. Under these circumstances, therefore, the shiftable element 52 will be connected with the gear 58 and consequently, ears 55 and 58 will be rotated thus effecting even wear between the bushing for said gear 58 and the driven shaft 58.

For each of the flve possible gear combinations just described, four separate and distinct gear combinations are adapted to be established in the primary unit Pu of the transmission by turning the plug valve 224 to four separate positions. Referring to Fig. 19, the plug valve 224 is provided with a boss 225 having a single radial port 284 that is adapted to be aligned with a passage 285 in communication with the bore I 28 of valve body I21 within which valve mechanism I33 is adapted to reciprocate. When the port 284 is in alignment with passage 285, fluid under pressure from bore 228 is admitted to the valve mechanism I33 forcing the lower part thereof downwardly, admitting fluid under pressure to the left side of the piston I M connected to the rod 88 whereupon shiftable element 43 is connected to gear 4I.

Referring to Fig. 20, plug valve 224 is provided with another boss 225 having a radial port 288 that is adapted to be moved into alignment with a passage 28'! that communicates with the bore l28 within which the. valve mechanism I33 is adapted to reciprocate. When this alignment is provided; the lower portion of valve I33 is moved downwardly and fluid under pressure is admitted to the right side of the piston I8I that is connected to the rod 88 whereupon shiftable element 43 is connected to gear 48 of the transmission.

Referring to Fig. 21, the plug valve 224 is additionally provided with a boss 225 having a radial passage 288 that is adapted to become aligned with a passage'288 that communicates with the bore I28 within which valve mechawards the left and thereby effecting disengagement of the clutch 29 and engagement of the brake 3|. While this is occuring, notches 210 and 280 (Fig. 23) become aligned with the de tents 216 and 211 whereupon the plug valves 223 and 224 may be manually turned by the handles 245 and 2 to provide any desired gear combination within the transmission. When a desired gear combination has been established, turning of the shaft 28! from right to left (Fig. 23) permits upward movement of the rocker arm 209 (Fig. 7) to thereby effect the intermittent admission and cut-ofi of fluid under pressure to the left side 'of piston member I28 to thereby incrementally shift the plunger II! to the right, effecting disengagement of the brake 3| and engagement of the clutch 29. At the same time, the notches 219 and 280 move out of registry with the detents 216 and 211 and maintain the plug valves 223 and 224 in their adjusted position. As previously explained, in connection with the description of the compound valve actuatin mechanism I 36 shown in Fig. 7, the incremental movement of the clutch 29 into driving engagement is directly proportional to the incremental movement applied to shaft 28L Accordingly, an hydraulically-operated clutch is provided that does not completely become engaged when the pressure is turned on, but one which moves toward or from engagement by increments proportional to the movements applied to the manual actuating mechanism. Such a clutch in a transmission is extremely valuable since it places the incremental rotary movement of the driven member directly under the control of the operator.

Although the various features of the improved transmission control have been shown and described in detail to fully disclose one embodiment of the invention, it is evident that numerous changes may be made in such details; and certain features may be used without others, without departing from the principles of the invention.

We claim:

1. A transmission comprising in combination, a driving member; a driven member; a plurality of gears between said driving and driven members; a clutch; means adapted to be operated for establishing various gear combinations between said driving and driven members; a control drum adapted successively to be indexed from point to point about its periphery and including means at each of said points for attaching replaceable elements for operating any of said gear-combination establishing means, whereby at each point of said drum any of said gear-combinations may be operated; and a power-operated control adapted to perform successive cycles of operation, said control including a member adapted to make a complete revolution for each of said cycles and adapted during each cycle successively to neutralize said clutch, to move said control drum from one point to its next succeeding point, and to engage said clutch.

2; A transmission comprising in combination, a driving member; a driven member; a plurality of gears between said driving and driven members; a clutch; a plurality of elements adapted to be operated in groups of certain of said elements, for establishing various gear combinations between said driving and driven members; a control drum adapted successively to be indexed from point to point about its periphery and including means at each of said points for attaching replaceable elements'for operating any of said gear-combination establishing elements,

whereby at each point of said drum any of said gear-combinations may be operated: and a power-operated control adapted to perform successive cycles of operation, said control including a member adapted to make a complete revolution for each of said cycles and adapted during each and including means at each of said points for attaching replaceable elements for operating any of said fluid-actuated means, whereby at each point of said drum any of said gear-combinations may be operated; and a power-operated control adapted to perform successive cycles of operation, said control including a member adapted to make a complete revolution for each of said cycles and adapted during each cycle of operation successively to neutralize said clutch, to move said control drum from one point to its next succeeding point, and to engage said clutch.

4. A transmissionv comprising in combination, a driving member; a driven member; a plurality of gears between said driving and driven members; a clutch; a brake; means adapted to be operated for establishing various gear combinations between said driving and driven members; a control drum adapted successively to be indexed from point to point about its periphery and including means at each of said points for attaching replaceable elements for operating any of said gear-combination establishing means, whereby at each point of said drum any of said gear-combinations may be operated; and a power-operated control adapted to perform successive cycles of operation, said control including a member adapted to make a complete revolution for each of said cycles and adapted during each cycle of operation successively to neutralize said clutch and engage said brake, to move said control drum from one point to its next succeeding point at a substantial time interval after said brake is engaged, and to disengage said brake and engage said *clutch.

5. A transmission comprising in combination, a driving member; a driven member; a plurality of gears between said driving and driven mem-,

bers; a clutch; a brake; a plurality of elements adapted to be operated in groups of certain of said elements, for establishing various gear combinations between said driving and driven members; a control drum adapted successively to be indexed from point to point about its periphery and including means at each of said points for attaching replaceable elements for operating any of said gear-combination establishing elements, whereby at each point of said drum any of said gear-combinations may be operated; and a power-operated control adapted to perform successive cycles of operation, said control including a member adapted to make a complete revolution for each of said cycles and adapted during each cycle of operation successively to neutralize said clutch and engage said brake, to move said 

